London's most famous cemetery, the final resting place of revolutionary socialist Karl Marx, is searching for a new lease of life by reclaiming long-abandoned graves so they can be sold again for fresh burials.

The Victorian-era Highgate Cemetery, crammed with a jumble of ivy-covered graves and ornate stone memorials, stretches across 37 acres (15 hectares) of north London and is a popular attraction, especially for left-wing visitors wanting to pay their respects at Marx's tomb.

In a practice that the father of Communism might not approve of, the graveyard charges an entry fee, because unlike most other cemeteries it is not funded by a local authority. But that income alone is not enough and the cemetery is hoping the extra burial capacity will generate the money it needs to remain a working graveyard.

"It's the biggest step that the cemetery has ever taken towards achieving a sustainable way forward," said Ian Dungavell, chief executive of the Friends of Highgate Cemetery Trust, which operates the site.

In many cases, so-called grave renewal involves lifting and reinterring earlier remains deeper in the ground to accommodate a second burial.

This was widely practised in the churchyards of medieval England and is routine elsewhere in Europe, but old graves are rarely reused in Britain today. Around 80% of Britons now choose to be cremated when they die.

Highgate, home to over 53,000 graves including those of singer George Michael and writer Douglas Adams, has earmarked an initial 460 graves that have not been used for 75 years or more.

The cemetery placed a notice last week on the front page of the Times newspaper, giving owners or kin six months to raise any objections.

With a burial plot costing anywhere from 5,000 pounds to 25,000 pounds ($6,300-$31,700) the grave renewal project - authorised by the Highgate Cemetery Act 2022 - is vitally important, Dungavell said.

"Without it, the real danger is it would have just become a spooky old graveyard of limited interest to anyone."

(Reporting by Sachin Ravikumar, Ben Makori and Hannah McKay; Editing by William James and Frances Kerry)